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Breakthrough: A new gauge for measuring a star’s surface gravity

Astronomers have just discovered a new method for measuring distant stars' gravitational pull, which could lead to the discovery of billions of new worlds.

There are countless stars in the observable universe, but astronomers only know a small fraction of them in any real sort of depth. According to a report from the BBC, however, this could be about to change.

Researchers from the University of Vienna in Austria have discovered a new method for determining a distant star’s gravitational pull, which has profound implications for studying its characteristics. According to study co-author Professor Jaymie Matthews, the new technique will allow astronomers to know how big and bright a star is, as well as if there are any planets orbiting within its habitable zone.

Using data collected by the Kepler space telescope, a team led by Professor Thomas Kallinger showed that by examining the variations in brightness of stars that are millions of light-years from the Earth, measurements of surface gravity could be fine-tuned to a degree never achieved before.

Surface gravity refers to the force that pulls objects towards the center of a much more massive object, like a star or a planet. By examining the surface gravity of distant suns that show similar characteristics to our own, astronomers hope to zoom in on planets that are the most likely to host the conditions necessary for life to develop.

A star’s mass and radius determine its surface gravity, and using the new method, astronomers can solve for the missing variables to learn how big the star is. This can help them estimate the temperature, age and type of star. It will allow researchers to search for solar systems with planets orbiting at a distance that would allow liquid water to exist – a key component of life.

This new method will help prevent false identifications of Earth-like planets at great distances because it will immediately offer a number of clues that show what type of star is being viewed.

“If you find a planet around a star that you think is Sun-like but is actually a giant, you may have fooled yourself into thinking you’ve found a habitable Earth-sized world,” says Professor Matthews. “If you don’t know the star, you don’t know the planet.”

The study, which was published in the journal Science Advances, can be found here.